True friendship is like sound health the value of it is seldom known until it is lost.

Success always necessitates a degree of ruthlessness. Given the choice of friendship or success, I'd probably choose success.

As iron sharpens iron, so a friend sharpens a friend.

It is not so much our friends' help that helps us, as the confidence of their help.

Since there is nothing so well worth having as friends, never lose a chance to make them.

Never explain - your friends do not need it and your enemies will not believe you anyway.

True friendship can afford true knowledge. It does not depend on darkness and ignorance.

One of the most beautiful qualities of true friendship is to understand and to be understood.

Friendship is unnecessary, like philosophy, like art... It has no survival value rather it is one of those things that give value to survival.

Friendship may, and often does, grow into love, but love never subsides into friendship.